1. Field of the Invention
This invention relates to an apparatus for recording and reproducing information on and from a recording medium.
2. Description of the Prior Art
Japanese published unexamined patent applications 56-163536. 57-6446, 57-212642, and 60-70543 disclose a recording medium having both a magnetic recording portion and an optical recording portion.
Japanese published unexamined patent application 2-179951 discloses a recording medium which has an optical recording portion and a magnetic recording portion at opposite sides thereof respectively. Japanese patent application 2-179951 also discloses an apparatus which includes an optical head facing the optical recording portion of the recording medium for reading out information from the optical recording portion, a magnetic head facing the magnetic recording portion of the recording medium for recording and reproducing information into and from the magnetic recording portion, and a mechanism for moving at least one of the optical head and the magnetic head in accordance with rotation of the recording medium. In the apparatus of Japanese patent application 2-179951, during the processing of the information read out from the magnetic recording portion, a decision is made as to whether or not the information recorded on the optical recording portion is necessary, and a step of reading out the information from the optical recording portion is executed when the information on the optical recording portion is decided to be necessary.
It is an object of this invention to provide an improved recording and reproducing apparatus.
A first aspect of this invention provides a recording and reproducing apparatus for use with a disk-shaped recording medium which includes a transparent substrate and an optical recording layer formed on the transparent substrate, the apparatus comprising a light source for emitting light; an optical head for applying the light to the optical recording layer from the light source via the transparent substrate, for focusing the light on the optical recording layer, and for reproducing information from the optical recording layer; a position detecting means for detecting at least one of a pit depth and a physical position of information which has a first given relation with a specified address and which is recorded on the recording medium, and for generating first positional information representing at least said one of the pit depth and the physical position; a reproducing means for reproducing a previously-recorded secret code from the recording medium, the secret code representing second positional information, and for decoding the secret code into the second positional information, the second positional information representing at least one of a predetermined reference pit depth and a predetermined reference physical position; a collating means for collating the first positional information and the second positional information, and for checking whether or not the first positional information and the second positional information are in a second given relation; and a stopping means for, in cases where the first positional information and the second positional information are not in the second given relation, stopping at least one of outputting of a reproduced signal of the recording medium, operation of a program stored in the recording medium, and decoding of the secret code.
A second aspect of this invention provides a recording and reproducing apparatus for use with a disk-shaped recording medium which includes a transparent substrate, and an optical recording layer and a magnetic recording layer formed on the transparent substrate, the apparatus comprising a light source for emitting light; an optical head for applying the light to the optical recording layer from the light source via the transparent substrate, for focusing the light on the optical recording layer, and for reproducing information from the optical recording layer; a magnetic head for recording a signal on the magnetic recording layer or reproducing a signal from the magnetic recording layer; a position detecting means for detecting a position of an address information recorded on the recording medium, and for generating first positional information representing said detected position of the address information; a reproducing means for reproducing a previously-recorded secret code from the recording medium, the secret code representing second positional information, and for decoding the secret code into the second positional information, the second positional information representing a predetermined reference position: a collating means for collating the first positional information and the second positional information, and for checking whether or not the first positional information and the second positional information are in a given relation: and a stopping means for, in cases where the first positional information and the second positional information are not, in the given relation, stopping at least one of outputting of a reproduced signal of the recording medium, operation, and decoding of the secret code.